Cup to be used as cap for thermos bottles



April 4, 1944. G. A. F. KOHRTZ v ,345,

CUP TO BE USED AS CAP FOR THERMOS BOTTLES Filed July 9, 1940 Patented Apr. 4, 1944 CUP TO BE USED AS CAP FOR THERMOS BOTTLES Gustaf Adolf Fredrik Kohrtz, Stockholm, Sweden Application July 9, 1940, Serial No. 344,595

In Sweden July 15, 1939 1 Claim.

The invention relates to an improved cap of mouldable material and the like which is particularly adapted for use as a cap on a heat insulated bottle, a so-called thermos bottle. It refers to that kind of cups which may be pushed into each other and by a turning movement secured to each other, thus enabling a plurality of cups to be united. This unity of cups may provide on a thermos bottle.

The above mentioned kind of cup has hitherto been made of metal with a conical screwthread so that an inner and an outer screwthread at the rim of the cup are obtained through pressing of the sheet-metal. Through a certain conicalness the screwthread on the outer side of one cup may be brought to fit in the screwthread on the inner side of another cup. This construction, however, cannot be used for cups made of mouldable material with relatively thick walls, as it would mean a very great conicalnes which would cause a little volume and unsatisfactory securing of the screwthread connection. These inconveniences are avoided in a cup according to the invention as the outer screwthread is displaced axially from the rim of the cup so that the said screwthread does not cover the inner screwthread and the screwthreads are almost cylindrical.

In the drawing a cup according to the invention is shown. The cup is provided with screwthreads I and 2 on the inner and outer sides respectively. The screwthreads have such a diameter that the screwthread I of one cup may be pushed into the screwthread 2 of another cup.

Owing to this it is necessary to push the screwthreads in relation to each other in the axial direction of the cup. The cup can be made of any suitable material, e. g., Bakelite or any other mouldable material. The securing device, 1. e., screwthreads or grooves are preferably preformed in such a way that the interlocking is quickly obtained with only a little turning movement and so that the cup is easily cleaned. The screwthreads which should be few and relatively shallow ought to have a great pitch.

I claim:

A cup of the type adapted to be placed in a nested relationship with a similar cup including a cup body havin interlocking screw-threaded portions on the inner and on the outer side of the cup, the screw-threaded portion on the inner side of the cup being situated below the rim and the screw-threaded portion on the outer side of the cup being situated at a distance from said rim which is greater than the length of said screw-threaded portion on th inner side of said cup, the screw-threaded portions on both sides of the cup having a cylindrical form and such dimensions and shape that the screw-threaded portion on the outer side of the cup fit the screwthreaded portion on the inner side of a similar cup, the Wall having a substantial thickness over 1 mm. (0.03937 inch) and being provided with an offset between the two screw threads, said ofi'set being substantially equal to the main thickness of the wall.

GUSTAF' ADOLF FREDRIK KOHRTZ. 

